Filtering appliance for cleaning cooking oil

Abstract

A filtering appliance for cleaning cooking oil in a food fryer is designed and dimensioned for single-handed portable use in "hand-gun" fashion. The appliance has an elongate casing means with a hand grip at one end adjacent a pump-and-motor assembly. An intake nozzle conducts oil to be cleaned to a cartridge style filter made by stacking annular elements cut from a commercially available filter material of fibrous mat forming matrix holding particulate filtering media. The filter is axially spring loaded to accommodate yielding of the filter material. The appliance discharges into the food fryer through a duct outside the casing means. Thus, the oil is recirculated to achieve cleaning.

We claim: 
     
       1. A filtering appliance comprising an elongate casing (17) defining an inwardly facing surface, a stack (29) of annular filter elements (30, 31) disposed within the casing (17) and defining an outwardly facing surface and a hollow core, the annular filter elements (30, 31) being of a compressible material so that the stack (29) has a length that is variable in use according to the magnitude of force acting on the stack in a longitudinal direction thereof, the inwardly facing surface of the casing being spaced from the outwardly facing surface of the stack, an abutment means (20) disposed within and fixed to the casing and abutted by one end of said stack, means defining a duct (22) disposed in said abutment means (20) for carrying fluid from the hollow core of the stack, fluid outlet means (15) for discharging filtered fluid from the appliance and communicating with said duct (22), closure means (27) defining mutually opposite faces of which one is in contact with an other end of the stack to prevent fluid flow directly into the hollow core of the stack, the closure means (27) being shiftable with respect to the casing (17) to enable the closure means to follow the said other end of the stack as the length of the stack varies in use, fluid inlet means (11, 23) providing access to the outwardly facing surface of the stack and to an other face of the closure means, a spring (25) arranged to act between the casing and the other face of the closure means and urging the closure means (27) to remain in contact with other end of the stack, and an elongate former (33) extending within the stack (29) and having the annular elements (30, 31) arranged thereon so that the annular elements (30, 31) and the former (33) are mutually relatively shiftable in the longitudinal direction thereof. 
     
     
       2. A filtering appliance according to claim 1, including pump means (21) associated with the casing (17) and operable to induce flow of fluid through said inlet means (11, 23) said filter (29) and said duct (22). 
     
     
       3. A filtering appliance according to claim 2, wherein the pump means (21) is disposed adjacent the abutment means (20) for drawing fluid through said duct (22). 
     
     
       4. A filtering appliance according to claim 3, including an electric motor (34) coupled to the pump means (35) for driving same. 
     
     
       5. A filtering appliance according to claim 4, including electronic sensing and switching means (35) connected to the electric motor (34) and operative to switch the motor off upon sensing a motor current in excess of a predetermined value. 
     
     
       6. A filtering appliance according to claim 1, wherein each annular element (30, 31) is cut from a sheet of filter material comprising a mat of fibres bonded together to form a matrix, and particulate filtering medium held in said matrix.